Specimen positioning apparatus for use with a back reflection x-ray camera

ABSTRACT

A specimen positioning apparatus is disclosed which permits translation of the specimen relative to a reference point in space. A plurality of interfitting members supported by the operating assembly permits positioning of the specimen in the Xand Y-directions. An independent member provides longitudinal or Z-axis positioning.

United States Patent I ['72] Inventor James F. Kreider [56] ReferencesCited 1 l N s g i UNITED STATES PATENTS [21 App o. Filed Nov. 19683,l05,90l 10/1963 Ladelleta]. 250/51.5 [45] Patented Jan. 12, 1971Primary Examiner-Archie R. Borchelt [73] Assignee Avco CorporationAssistant Examiner-A. L. Birch Cincinnati, Ohio AttorneysCharles M.Hogan and Eugene C. Goodale a corporation of Delaware [54] SPECIMENPOSITIONING APPARATUS FOR USE WITH A BACK REFLECTION X-RAY CAMERA 3ClaunS6Drawmg ABSTRACT: A specimen positioning apparatus is disclosed[52] [1.8. CI 250/515, which permits translation of the specimenrelative to a 250/495 reference point in space. A plurality ofinterfitting members [51] Int. Cl G0lh 23/20 supported by the operatingassembly permits positioning of [50] Field of Search ..l ..250/49.5(2),the specimen in the X- and Y-directions. An independent member provideslongitudinal or Z-axis positioning.

PATENTEB JAN] 2 ran SHEET 1 [IF 2 INVENTOR. JAMES F. KREIDERPATENTEUJANIZIB?! 3.555275 SHEET 2 BF 2 INVENTOR. JAMES F. KRE IDER W ATEYS' SIECIMEN IOSITIONING APPARATUS FOR USE WITH A BACK REFLECTION X-RAYCAMERA BACKGROUND OF THE INVENTION This invention pertains to specimenholding apparatus and more particularly to an adjustable apparatus forproviding specimen translation relative to a given point in space.

In many applications in industry, it is desirous to examine the entiresurface area of an object or specimen when the area under examination atany given instant is very small as compared to the entire surface. Oneexample of this type examination is in the determination of crystalorientation necessary in the production of such items as silicon andgermanium semiconductors.

In order to fully examine the entire surface area, it is necessary tomove the specimen relative to the examining media. In some instances,the examining media may be moved while the specimen is held in place.This is undesirable because very often the examining media andassociated structure are very large as compared to the specimen.

In some cases the examining media is fixed, such as in X-rayinvestigation when used in a back reflection X-ray camera of the GriakLaue type. Because of the fixed examining media, the specimen must bemoved. It is important, however, that the specimen-to-film (in the X-rayinvestigation) or specimento-examining media distance is not disturbedwhen adjustments are made, thus, eliminating the necessity ofrealignment. In the past, when examining a crystal specimen with a GriakLaue back reflection camera, it has been necessary to remove and remountthe specimen, on a mounting piece in order to examine a differentportion of the specimen. This is not only time consuming and costly, itfrequently requires the realignment of the specimen relative to theexamining media.

It is an object of the invention to provide a specimen-positioningapparatus which overcomes the previous problems involved and will permitspecimen translation relative to a given point in space withoutdisturbing the specimen-to-film, etc., distance.

Another object of the invention is to provide specimen positioningapparatus which is inexpensive to manufacture and requires very littletime to make an adjustment of the position of the specimen.

A further object of the invention is to provide a specimen positioningapparatus which can be used as a compatible accessory with a backreflection X-ray camera.

SUMMARY OF THE INVENTION A specimen-positioning apparatus is providedwhich is mounted in an operating assembly having means for establishinga reference point in space relative to a point on the specimen. Thespecimen-positioning apparatus provides for two axes of adjustment ofthe specimen relative to the reference point in space so that the entiresurface area may be examined. Cooperating members of thespecimen-positioning apparatus permit independent axis movement withoutdisturbing the specimen-to-film distance and means are provided forsecuring the cooperating members, and hence the specimen, in anyadjusted position.

DESCRIPTION OF THE DRAWINGS An illustrative embodiment of the presentinvention is shown in the following drawings, in which:

FIG. 1 is a perspective view of the specimen-positioning apparatusmounted in an operating assembly;

FIG. 2 is an exploded perspective view of the specimenpositioningapparatus;

FIG. 3 is a sectional side view of the specimen-positioning apparatus;

FIG. 4 is a sectional top view of the specimen-positioning apparatus;

FIG. 5 is a perspective view of a second configuration of the rear slidemember; and

FIG. 6 is a perspective view of a second configuration of the middleslide member.

DETAILED DESCRIPTION OF THE INVENTION In the exemplary embodiment ofFIG. I there is shown an operating assembly representative of agoniometer or specimen mount for a Griak Laue back reflection X-raycamera. The operating assembly involved in accordance with the inventionfacilitates the movement of a specimen 12, held by the specimenpositioning apparatus shown generally at 14, through an arc, eithervertically or horizontally, with a high degree of accuracy. The elements7 and 8 functionally and schematically represent the well-known priorart structure (which need not be shown in detail herein) for positioningthe collar 16 in elevation and azimuth. That is, the position of thecollar 36 in azimuth or its angular displacement is controlled by theangular position of the base 7(Additionally, the position of thespecimen in elevation or depression is controlled by fixing the angularrelationship between lug or pivot point 8 and the vertical. In otherwords, the collar 16 is, by prior art means, adjustable over ahorizontal are or a vertical arc, as shown. The specimen-positioningapparatus 14 is positioned along the Z-axis in a manner to be explainedherebelow. The proper specimen position relative to elevation, azimuth,and distance, Le, a reference point in space coinciding with theintersection of the X-, Y-, and Z-axes, is obtained by any suitablemeans such as by viewing the specimen from the side along line 9 througha magnifier lens (not shown) on the side of the operating assembly.

It will be understood that the magnifier referred to above is employedto establish the initial position of the specimen along the Z-axis. Itwill be understood that a line of sight is established for purposes ofexamining the specimen. That line of sight happens to conform to theZ-axis 'as illustrated in FIG, 1 and is established by optics well-knownin the art and not here shown. The lateral displacement of the specimen,in two dimensions, provided in accordance with the invention, permitsany elemental area of the specimen to be placed in this line of sight sothat the examination of the specimen is greatly facilitated, It isfurther understood that the axes referred to herein are referenced tothe specimen carrying subassembly or positioning apparatus 14. Hence,the Z-axis coincides with the longitudinal axis of the collar 16.

The preferred illustrative embodiment of the specimenpositioningapparatus is best seen in FIGS. 2-4 in which a cylindrical or othershaped collar 16 is adapted to be mounted in the operating assembly andheld immobile by any suitable means. An extension member 18, having anouter surface conforming with the inner surface of the collar 16, ismounted in collar 16 for movement in the Z-axis. In the embodimentshown, it is seen that collar 16 and extension member 18 are ofcylindrical shape. Extension member 18 is coaxially mounted in collar 16and is adapted for reciprocal and rotational displacement therein. Screwmeans (not shown) is threadably mounted at 20 in collar 16 and extendsthrough the collar inner surface to frictionally engage member 18 andlock the member against further movement. The screw is preferably madeof nylon or similar-type material so that the outer surface of member 18is not scratched or marred.

One end of the extension member 18 extends beyond the end of collar 16and has a groove or slot 22 formed therein perpendicular or transverseto the longitudinal or Z-axis of member 18, In this embodiment, a T-slotis shown, but it is understood that other configurations, such asdovetail, etc., may

be used.

A second or intermediate member 24 has one end formed with an integralslider complementary to and slidable within slot 22 for adjustablemovement therealong in the Y-axis and transverse the Z-axis. Theintermediate member 24 has a slot 26 at the other face which isangularly displaced at relative to the slider. A front orspecimen-holding slider member 28, upon which specimen 12 is suitablymounted, is formed complementary to slot 26 and slidably mounted thereinfor adjustable movement in the X-axis. Hence, by moving members 24 and28, the specimen 12 is adjustable along the X- and Y- axes without thenecessity of removing the specimen and remounting it at a differentspot.

A longitudinally extending cavity or cylindrical hole 30 is formed inthe intermediate member 24. The cavity 30 opens into slot 26 and extendsinwardly along the Z-axis forming the cylinder for a piston 32 having arounded end. A locking screw 34, terminating in a beveled end, isthreadably mounted in member 24 for engagement with the rounded end ofpiston 32. Thus, as the locking screw 34 is tightened in member 24, thebeveled end of the screw forces the piston 32 to frictionally engage andlock the specimen-holding member 28 in place. In order to avoid marringmember 28, the piston 32 may be made of nylon or similar material. 7 Theintermediate member 24 is locked in position relative to the rear member18 by any suitable means such as locking screw 36 which is threadablymounted in member 18 along the longitudinal axis thereof and extendsinto frictional engagement with the complementary surface of member 24.

A rear stop member 38 is mounted in one end of collar 16 and is lockedby any suitable means such as a nylon or similartype setscrew (notshown) threadably mounted in the collar at 40 for frictional engagementwith member 38.

In operation, the rear member 18 is positioned in the collar 16 to theproper distance along the Z-axis by means of viewing the specimenthrough the magnifier lens on the operating assembly. The rear member 18is then locked in place with the locking means at 20. The rear stopmember 38 is positioned in the collar 16 so that it is touching the rearmember 18 and then locked in place with the lock means at 40. Ifdesired, the lock means at 20 can be loosened and the rear member 18 canbe rotated in the collar 16 without altering the position of thespecimen along the Z-axis. To move the specimen so that other parts ofthe specimen surface area coincide with the reference point in space,i.e., the intersection of the three axes, it is only necessary to loosenthe respective screws 34 and 36 and move members 28 and 24 along the X-and Y-axes. A modification of the rear and intermediate members is shownin FIGS. and 6 in which middle member 42 has a key or lug 43 adapted toslidably fit in slot 44 of rear member 46. Member 42 is locked in placeby a loclt screw (not shown) threadably mounted in rear member 46 at 48.A slot 50 is formed in member 42 transverse the key 43 for receiving aspecimen holding member (not shown). A plurality of locking means, suchas setscrews, are provided at 52, 54 and 56 for frictionally engagingthe specimen holding member and locking it in place. It is seen thatthis modification also permits movement of a specimen along the X- andY-axes.

[t is thus seen that the objectives of this invention have beenaccomplished. A specimen positioning apparatus has been described whichwill permit lateral translation of the specimen in two dimensions withreference to a point in space without disturbing the specimen locationalong the Z-axis.

While the forms of apparatus herein described constitute preferredembodiments of the invention, it is to be understood that the inventionis not limited to these precise forms of apparatus.

lclaim:

1. in an operating assembly of the type including specimenpositioningapparatus and means for adjusting the angle of elevation and the angleof azimuth of the specimen-positioning apparatus to establish a givenreference point in space, the improvement in the specimen-positioningapparatus to provide specimen translation relative to a given referencepoint in space comprising:

a first member coaxially mounted within the operating assembly andhaving an outer surface complementary with the operating assembly innersurface, said first member having one end thereof extending beyond saidoperating assembly and having a first slot formed therein transverse thelongitudinal axis thereof;

a second member formed with a slider complementary to said slot andslidably mounted therein for adjustable displacement therealongtransverse the longitudinal axis, v said second member having a slotformed in the opposite end thereof transverse the complementary slider,said second member being further formed with a longitudinal cavityopening in said slot;

means for securing said second member in any adjusted position relativeto said first member;

a specimen-holding member mounted on said second member for relativemovement therewith transverse the direction of said second membermovement wherein a specimen mounted thereon is adjustably moveable intwo directions relative to said first member whereby any element of theentire specimen may be positioned coincident to the longitudinal axis ofthe apparatus;

a friction member mounted in said cavity for a reciprocal longitudinalmovement therealong; and

a lock screw mounted in said second member transverse the longitudinalaxis thereof and extending into said cavity area for cooperativeengagement with said friction member whereby tightening said screw willforce said friction member outward into frictional engagement with saidspecimen-holding member thereby securing said specimen-holding member inany adjusted position relative to said second member.

2. Apparatus as set forth in claim 1 further comprising:

a collar adapted to be mounted in the operating assembly and having aninner surface complementary with said first member outer surface whereinsaid first member is mounted in said collar with the one end thereofextending beyond said collar;

said specimen-holding member being formed with a slider complementary tothe slot in said second member and slidably mounted therein foradjustable displacement therealong; and

a stop member coaxially mounted within said collar and adapted forabutting engagement with said first member wherein said first member maybe precisely positioned along the longitudinal axis relative to saidcollar and whereby the relative transverse movements of said secondmember and said specimen-holding member pro vides translation of thespecimen in a given plane transverse the longitudinal axis thereof.

3. In an operating assembly of the type including specimenpositioningapparatus and means for adjusting the angle of elevation and the angleof azimuth of the specimen-positioning apparatus to establish a givenreference point in space, the improvement in the specimen-positioningapparatus to provide specimen translation relative to a given referencepoint in space comprising:

a cylindrical collar adapted'to be mounted in the operating assembly andhaving a cylindrical inner surface;

a cylindrical first member coaxiaily mounted within said collar forlongitudinal and rotational movement relative to said collar, said firstmember having one end thereof extending beyond one end of said collarand having a first slot formed in the extended end transverse thelongitudinal axis thereof; I

means for securing said first member in any longitudinal and rotationalposition relative to said collar;

a second member formed with a slider complementary to said slot andslidably mounted therein for adjustable displacement therealongtransverse the longitudinal axis;

a screw threadably mounted in said first member along the longitudinalaxis and extending into said first slot for frictional engagement withsaid second member for securing said second member in any adjustedposition relative to said first member;

said second member having a second slot formed in the face opposite theslider and transverse thereto, said second member further having acavity formed therein along the longitudinal axis and opening into saidsecond slot;

a specimen-holding member formed with a slider complementary to saidsecond slot and slidably mounted therein for adjustable displacementtherealong wherein a specimen mounted thereon is adjustably moveable intwo directions relative to said first member whereby any element of thespecimen may be positioned coincident to the longitudinal axis of theapparatus;

a piston mounted in said second member cavity for a reciprocallongitudinal movement therealong; and

piston outward into frictional engagement with said specimen holdingmember thereby securing said specimen-holding member in any adjustedposition relative to said second member.

1. In an operating assembly of the type including specimenpositioning apparatus and means for adjusting the angle of elevation and the angle of azimuth of the specimen-positioning apparatus to establish a given reference point in space, the improvement in the specimen-positioning apparatus to provide specimen translation relative to a given reference point in space comprising: a first member coaxially mounted within the operating assembly and having an outer surface complementary with the operating assembly inner surface, said first member having one end thereof extending beyond said operating assembly and having a first slot formed therein transverse the longitudinal axis thereof; a second member formed with a slider complementary to said slot and slidably mounted therein for adjustable displacement therealong transverse the longitudinal axis, said second member having a slot formed in the opposite end thereof transverse the complementary slider, said second member being further formed with a longitudinal cavity opening in said slot; means for securing said second member in any adjusted position relative to said first member; a specimen-holding member mounted on said second member for relative movement therewith transverse the direction of said second member movement wherein a specimen mounted thereon is adjustably moveable in two directions relative to said first member whereby any element of the entire specimen may be positioned coincident to the longitudinal axis of the apparatus; a friction member mounted in said cavity for a reciprocal longitudinal movement therealong; and a lock screw mounted in said second member transverse the longitudinal axis thereof and extending into said cavity area for cooperative engagement with said friction member whereby tightening said screw will force said friction member outward into frictional engagement with said specimen-holding member thereby securing said specimen-holding member in any adjusted position relative to said second member.
 2. Apparatus as set forth in claim 1 further comprising: a collar adapted to be mounted in the operating assembly and having an inner surface complementary with said first member outer surface wherein said first member is mounted in said collar with the one end thereof extending beyond said collar; said specimen-holding member being formed with a slider complementary to the slot in said second member and slidably mounted therein for adjustable displacement therealong; and a stop member coaxially mounted within said collar and adapted for abutting engagement with said first member wherein said first member may be precisely positioned along the longitudinal axis relative to said collar and whereby the relative transverse movements of said second member and said specimen-holding member provides translation of the specimen in a given plane transverse the longitudinal axis thereof.
 3. In an operating assembly of the type including specimen-positioning apparatus and means for adjusting the angle of elevation and the angle of azimuth of the specimen-positioning apparatus to establish a given reference point in space, the improvement in the specimen-positioning apparatus to provide specimen translation relative to a given reference point in space comprising: a cylindrical collar adapted to be mounted in the operating assembly and having a cylindrical inner surface; a cylindrical first member coaxially mounted within said collar for longitudinal and rotational movement relative to said collar, said first member having one end thereof extending beyond one end of said collar and having a first slot formed in the extended end transverse the longitudinal axis thereof; means for securing said first member in any longitudinal and rotational position relative to said collar; a second member formed with a slider complementary to said slot and slidably mounted therein for adjustable displacement therealong transveRse the longitudinal axis; a screw threadably mounted in said first member along the longitudinal axis and extending into said first slot for frictional engagement with said second member for securing said second member in any adjusted position relative to said first member; said second member having a second slot formed in the face opposite the slider and transverse thereto, said second member further having a cavity formed therein along the longitudinal axis and opening into said second slot; a specimen-holding member formed with a slider complementary to said second slot and slidably mounted therein for adjustable displacement therealong wherein a specimen mounted thereon is adjustably moveable in two directions relative to said first member whereby any element of the specimen may be positioned coincident to the longitudinal axis of the apparatus; a piston mounted in said second member cavity for a reciprocal longitudinal movement therealong; and a lock screw threadably mounted in said second member transverse the longitudinal axis thereof and extending into said cavity area for cooperative engagement with said piston whereby tightening said screw will force said piston outward into frictional engagement with said specimen holding member thereby securing said specimen-holding member in any adjusted position relative to said second member. 